Bladder protocol compliance and its effect on radiation enteritis among cervical cancer patients at Ocean road cancer institute

Abstract

ABSTRACT Background: Cervical cancer is the 4th most common cancer in women worldwide and a leading cause of cancer morbidity in Tanzania. Radiotherapy is the primary treatment for locally advanced Cancer of the cervix. One of the most important complications of pelvic irradiation is radiation enteritis manifesting as an early effect and late effect. Advancement in radiotherapy has brought about tremendous improvement in target volume conformity using techniques such as Intensity Modulated Radiotherapy and the use of PROTON therapy. Due to limited access to these innovations many centers, including Ocean Road Cancer Institute, are not able to employ these newer techniques. As a result, there lies a challenge in minimizing exposure to the organs at risk. While the use of bladder protocol enhances reproducibility in EBRT during cervical cancer treatment, it also plays a vital role in pushing the bowel bag out of the radiation field. In Ocean Road Cancer Institute, Bladder protocol is a component of the daily treatment procedure for cervical cancer radiotherapy. However, there is a paucity of data on how well patients can comply with bladder instructions from simulation to the 25th session of treatment. With a majority of patients reporting enteritis-related complaints during treatment, it is important to determine the bladder protocol compliance pattern and its relation with grades of enteritis across all weeks of External Beam Radiotherapy. Objective: To assess bladder protocol compliance and its effect on the development of radiation enteritis among cervical cancer patients treated with radiotherapy at Ocean Road Cancer Institute. Materials and Methods: This was a single hospital-based prospective cohort study, conducted entirely in Ocean Road Cancer Institute from October 2022 to April 2023. The study population consisted of histologically confirmed cervical cancer patients receiving Teletherapy during the stipulated period and meeting the eligibility criteria. A total of 79 patients were recruited and followed from baseline to their last week of external beam radiotherapy. Endpoint was the weekly highest grade of enteritis. Bladder volume estimation by urine volume was used to check for compliance whereas, Common Terminology Criteria for Adverse Events scale was used to grade enteritis. Statistical Package for Social Science was used for analysis. Quantitative data were summarized using mean, standard deviation, and percentages. Comparison between bladder volumes from baseline to the last week of treatment was obtained using Analysis of Variance (ANOVA) for repetitive variables. Correlation between weekly bladder protocol compliance and weekly grade of enteritis was obtained using Spearman’s correlation method whereas the significance in the difference of proportion between different grades of enteritis weekly was obtained using CHI square test. P-value of <0.05 was considered statistically significant. Results: The mean urine volume at simulation was 296(+ 190 SD) while at week 5 the mean urine volume was 231.2 (+ 162 SD) which represented a 21.9% drop from baseline with a P-value of 0.003. There was an increment in mean bladder volume by 4% and 1% in weeks 1 and 2 respectively with p-values of 0.201 and 0.745 respectively. In weeks 3 and 4, the mean urine volume dropped by 12.7% and 15.3% respectively, with p-values of 0.011 and 0.009 respectively. The highest grade enteritis was grade I(5%), III(1%), III(4%), III(16%) and III(4%) in weeks 1,2,3,4 and 5 respectively with p-value of <0.001. correlation between mean weekly urine volume and grade enteritis yielded an inverse relationship with increasing strength of association towards week 5 and a p-value of 0.001 from weeks 2-5. Conclusion: Patients are less compliant with bladder protocol toward the last weeks of external beam radiotherapy. These could be due to dose-related toxicity such as radiation-induced cystitis or inadequate reinforcement of the bladder protocol practice. More severe forms of radiation-induced enteritis are relatively higher in the last three weeks of treatment. Poor bladder protocol compliance in weeks 3-5 is associated with increased grade 2 and 3 enteritis in the respective weeks of treatment.